1. Field of the Invention
Aspects of the present invention relate to a flexible circuit board of a liquid crystal display device, and in particular, to a flexible circuit board of a liquid crystal display device having a light absorbing layer.
2. Description of the Related Art
Generally, a liquid crystal display device is one of several flat display devices to display images. The liquid crystal display device displays the images by using a liquid crystal. The liquid crystal display device is advantageous in that it is thin and light compared with other display devices, requires a low driving voltage, and consumes little power. Accordingly, the liquid crystal display device has been widely used in all fields of industry.
Such a liquid crystal display device includes a thin film transistor (hereinafter, referred to as TFT) substrate, a color filter substrate opposing the TFT substrate, and a liquid crystal display panel that includes a liquid crystal which changes the transmission amount of light according to an electrical signal applied thereto.
Further, a driving module is coupled to the liquid crystal display device to apply an electrical signal to drive the liquid crystal display panel coupled to the liquid crystal display device. For this purpose, a flexible circuit substrate is disposed between the liquid crystal display panel and the driving module.
Since the liquid crystal that is included in the liquid crystal display panel can not emit light by itself, the liquid crystal display panel needs a light source to supply light having a brightness exceeding a predetermined level in order to display an image.
A high brightness light emitting diode has recently come into use as a light source for medium and/or small sized devices such as a mobile phone, a PMP (portable multimedia player) and a digital camera to enable the thickness and the weight of the noted devices to be thinner and lighter. As an example, such a light source is coupled to the flexible circuit substrate, and the light emitted from the light source is transmitted to a light guide plate arranged on the back side of the liquid crystal display panel.
In the above devices, light emitted from the light source that is mounted on the flexible circuit substrate should be transmitted to the light guide plate. However, some of the light is not transmitted to the light guide plate, but is transmitted to unwanted regions of the flexible circuit substrate. That is, since a conductive pattern is formed on the flexible circuit substrate, and passive elements such as a resistor and a capacitor are mounted, light emitted from the light source is transmitted to the conductive pattern or the passive elements. Because light emitted from the light source includes the energy of a regular or certain intensity, and the energy thereof affects the conductive pattern and the passive elements, the passive elements and the liquid crystal display panel malfunction. Therefore, though the structure in which the light source is mounted on the flexible circuit substrate is a technology that should be employed to address the recent trend towards use of slim and light-weight devices, since light emitted from the light source causes various passive elements to malfunction, the technology employing the above has a problem in that reliability thereof deteriorates.